com.tailf.dp

Interface DpActionCallback

All Known Implementing Classes:

ActionCallbackProxy

public interface DpActionCallback

This interface is used for the user actions callbacks.

Actions are specified in the data model (see tailf_yang_extensions(5)). The actionpoint specifies that the action is implemented as a callback function.

Unlike the callbacks for data and validation, there is no transaction associated with an action callback. However an action is always associated with a user session (NETCONF, CLI, etc), and only one action at a time can be invoked from a given user session. Hence the associated DpUserInfo is passed to the callbacks.

See Also:

Dp.registerAnnotatedCallbacks(Object)

Field Summary

Fields

Modifier and Type	Field and Description
static int	M_ABORT
static int	M_ACTION
static int	M_COMMAND
static int	M_COMPLETION
static int	M_INIT

Method Summary

Modifier and Type	Method and Description
void	abort(DpActionTrans actx) The abort() callback will be called for user initiated abort of an action.
ConfXMLParam[]	action(DpActionTrans actx, ConfTag name, ConfObject[] kp, ConfXMLParam[] params) The action() callback receives all the parameters pertaining to the action: The name argument is a pointer to the action name as defined in YANG model, the kp argument gives the path through the XML tree, and finally the params argument is a representation of the params element of the XML instance document provided with the invocation.
String	actionpoint() Return the name of the action point.
String[]	command(DpActionTrans actx, String cmdname, String cmdpath, String[] params) The command() callback is invoked for CLI callback commands.
Completion	completion(DpActionTrans actx, char cliStyle, String token, char completionChar, ConfObject[] kp, String cmdPath, String cmdParamId, ConfQname simpleType, String extra) The completion() callback is invoked for CLI completion and information.
void	init(DpActionTrans actx) Similar to the init() callback for external data bases.
int	mask() Mask of flags for each method that is supported by this callback

Field Detail

M_INIT

static final int M_INIT

See Also:

Constant Field Values

M_ABORT

static final int M_ABORT

See Also:

Constant Field Values

M_ACTION

static final int M_ACTION

See Also:

Constant Field Values

M_COMMAND

static final int M_COMMAND

See Also:

Constant Field Values

M_COMPLETION

static final int M_COMPLETION

See Also:

Constant Field Values

Method Detail

mask

int mask()

Mask of flags for each method that is supported by this callback

actionpoint

String actionpoint()

Return the name of the action point.

init

void init(DpActionTrans actx)
   throws DpCallbackException

Similar to the init() callback for external data bases. This socket will be used for the invocation of the action() callback, which implements the actual action. However note that unlike the callbacks for external data bases and validation, both callbacks are registered for each action point (i.e. different action points can have different init() callbacks), and there is no finish() callback - the action is completed when the action() callback returns.

Parameters:

actx - Action transaction context

Throws:

DpCallbackException - Callback method failed.

abort

void abort(DpActionTrans actx)
    throws DpCallbackException

The abort() callback will be called for user initiated abort of an action. The abort() callback will be called in a separate thread from the thread that is executing the action() callback. It is the responsibility of the abort() call to stop the action thread execution. There are two ways that the action() execution could be terminated. The simple solution is that the action() implementation itself checks the action transaction state by a call to DpActionTrans.getActionState(). In this case the abort() can have an empty implementation since the state will implicitly be set to DpActionTrans.STATE_ABORTED. However the above scenario is often not sufficient because the action() execution thread is busy and not able to check the state. In this case, the abort() callback needs to get hold of the execution action() thread and intervene to stop the execution. To be able to do this there need to be some information carried in DpActionTrans instance that makes this possible. Here using the DpTrans.getTransactionUserOpaque() is recommended. For instance the action() callback can initially call DpTrans.setTransactionUserOpaque(Object) with the object being the current thread using Thread.currentThread(). The abort() can then retrieve that Thread using DpTrans.getTransactionUserOpaque() and make a Thread.interrupt() call, under the assumption that the action() implementation is sensitive to interrupts and handles InterruptedException.

Parameters:

actx - The DpActionTrans instance, same as for the running action.

Throws:

DpCallbackException

action

ConfXMLParam[] action(DpActionTrans actx,
                      ConfTag name,
                      ConfObject[] kp,
                      ConfXMLParam[] params)
               throws DpCallbackException

The action() callback receives all the parameters pertaining to the action: The name argument is a pointer to the action name as defined in YANG model, the kp argument gives the path through the XML tree, and finally the params argument is a representation of the params element of the XML instance document provided with the invocation.

Parameters:

actx - Action transaction context

name - Action name

kp - Keypath array. kp[0] is the leaf.

params - Action parameters

Throws:

DpCallbackException - Callback method failed.

command

String[] command(DpActionTrans actx,
                 String cmdname,
                 String cmdpath,
                 String[] params)
          throws DpCallbackException

The command() callback is invoked for CLI callback commands. As the parameters in this case are all in string form, they are passed as an array of strings.

Parameters:

actx - Action transaction context

cmdname - Command name

cmdpath - Command path

params - Command parameters

Throws:

DpCallbackException - Callback method failed

completion

Completion completion(DpActionTrans actx,
                      char cliStyle,
                      String token,
                      char completionChar,
                      ConfObject[] kp,
                      String cmdPath,
                      String cmdParamId,
                      ConfQname simpleType,
                      String extra)
               throws DpCallbackException

The completion() callback is invoked for CLI completion and information. It must result in a Completion class instance. It is invoked for yang model elements with the directive tailf:cli-completion-actionpoint as well as model list elements with directives tailf:cli-custom-range-actionpoint or tailf:cli-custom-range-enumerator. Also for the corresponding directives in a clispec.

Parameters:

actx - Action transaction context

cliStyle - One of J, C or I for juniper, cisco-xr or cisco-ios

token - Parameter of the CLI command line that the callback invocation pertains to

completionChar - The char the user typed on of '\t', '?' or ' '

kp - Identifies model element path that the callback pertains to or null if not applicable

cmdPath - String giving the full path of the command

cmdParamId - The cli-completion-id if such is given in yang model or clispec.

simpleType - If the invocation pertains to an element that has a type definition, the simpleType identifies the type

extra - The extra argument is currently unused (always null).

Returns:

Completion object with the relevant completion structure.

Throws:

DpCallbackException